Centrifugal pump.



G. W. PRICE.

GENTRIPUGAL PUMP. APPLIUATION FILED 00T. zo, 1909. RENEWED PEB. 24, 1913.

, Patented Sept. 9, 1913.

..3 NM .ww e /w .Q N 4W* 0 lo 4. .I 6 e y O Application iled October 20,1909,`Seria1 No. 523,672. Renewed February 24, 1913.

. and useful Improvements in Centrifugal OFFICE,

Gonna w. PRICE, or SAN FRANCISCO, 'CALIFORNIA CENTRIFUGAI. PUMP.

To all 'whom t may'concern:

Be it known that I, GoMER W. PRICE, a citizen of thel United States, residing in the city and county of San Francisco and State of California, have invented certain new Pumps, hof which the following is a specification.

My invention relates to the class of cen-` trifugal pumps, and while applicable to all such pumps in which end-thrust exists, due to diercnce in pressure on opposite sides of the in ipeller or runner, it is particularly intended for centrifugal pumps of the inclosedimpeller type in' which such end-thrust is experienced to a greater extent.

The object ofmy invention is to overcome this end-thrust; and to this end my inven' tion consists in. the novel construction and i arrangement of parts which I shall herein-,

after fully describe', by reference to the accompanying drawings in which- Figure l is a vertical section of my 1m- 'proved centrifugal pump, showing one formv of specific construction of the two sides or walls of the throat of the collection chamber. Fig. 2 is a sectional detail ofthe collection chamber showing another construe` tive form of thethroat sides, the impeller being shown as affected by pressure on its suction side to cause it to move to afford relief by opening a passage to the clearance space on the opposite side. Fig. 3'is a sectional detail of the same parts of Fig. 2, but showing the opposite movement of the impeller and the consequent relief on the other side.

The pump here shown is one in which the impeller is mounted to rotate-in a-vertical plane on a horizontal axis, but it may be one in which a mounting at right angles is had, that is, with the impeller shaftvertical.

1 is a bed, in the standards 2 of which are suitable bearings 3 in which is journaled the impeller shaft 4 in l'such manner as to have a `slight. longitudinal movement.

. into the eye of the impeller.

9 are the clearance spaces between the faces of the -impeller and shell on opposite sides, and 10 are passages in the rear side of the impeller which permit any water Specification of Letters Patent.

- Patented sepas, 1913.

Serial No. 750,417.

which may collect there,l'especially .under pressure, to go through the impeller into the collection chamber.

11 are packing rings to form joints be-V tween the necks 12 of the impeller hub and esY the flanges 13 of the shell faces. These packing rings or joints may be of any suitable ch'aractertending to prevent-leakage. They are here-indicated as those of the Pat ent No. 834,848, granted Oct. 30, 1906, upon my application, their function being to prevent or to tend to prevent the water from escaping from the two sides of the impeller, or from the clearance spaces into the passages 10 or into the suction inlet 8.

14 is a side plate in the shell which permits -of the introduction of the impeller.

15 are annular 'projections in the two sides of the throat 16 of the collection chamber 6. In some cases, as in Fig. l, these projections are formed as rings, say of steel,

separate from the casing and are inserted in place. In other cases, as in Figs. 2 and 3, the projections are integral part-s of the casing. The adjacent faces of these throat projections are parallelplane surfaces, the dis-V tance between said faces being equal to the .distance between opposite walls-of the impeller blades. Their outer faces are chamfered or beveled down to an edge as shown. The periphery of the impeller is turned perfectly round, true and smooth, the disks being finished of uniform thickness. The peripheries 'of `the impeller disks just reach and touch the edges of the throat projections 15.

The efficiency and reliability of a well designed and well built centrifugal pump are due in great part' 'to the prevention of water ley-passing from the collection chamber to the suction inlet, and to overcoming the lend-thrust ofthe impeller, due to these leakages. Much success in this line has heretofore followed the provision and use of the packing rings 1l, tending to make nonfleakage joints; and if there were no leakages through these joints, the impeller would run inA perfect hydraulic balance. But inasmuch as it is absolutely impossible to maintain a joint without some leakage,

are never alike, and there always exists an end-thrust toward the side or end that leaks the greatest quant-ity.v Y

The purpose and effect of my present improvenient will now be clearly appreciated.`

vthe leakageon the two sides of the impeller has here been converted into velocity,

when properly First-it avoids excessive pressure in the clearance spaces each side of the impeller, by decreasing leakage. The pressure in these Spaces is directlydue and equal to theJ discharge or pressure head less what slight reduction may besuffered by the friction of the impeller disk on the inner surface of the water in said clearance spaces. The decrease of leakage into the clearance spaces is eected by my present improvement by the annular throat-projections l5 coacting with the peripheral surfaces of the'impeller disks. The water at this pointhas little or no pressure, as all the energy given to it and, confined, exerts but slight pressure in any direction other than radial; hence, when so confined, -there is but slight tendency to How in any other direction, the result being that when the pump is in operation, the pressure in the two clearance spaces is considerably less than that due to the discharge or pressure head. Y, Second-if, due to a variation of pressure between the two sides of the impeller, or inl the case of a pump having a vertical shaft with the weight of the moving parts to care for, the impeller is caused to move out of its central position shown in Fig. 1 to a position on one side as in Fig. 2, or on the other side as in Fig. 3, a passage will be opened to one or the other clearance space, between one of the throat projections A15 and the peripheryV of one of the impeller disks, through which, as shown by the arrows, a sufficient amount of water will be admitted to the proper side of the impeller to bring it back into alinement again. The impeller is thus balanced, with but little loss of water or loss of horsepower, The total end play of the impeller and shaft in extreme conditions which would cause the impeller to travel from one sidel to the other is slight.

Having thus described my invention what is claimed as new and desired to be protected by Letters Patent is In a centrifugal pump, the combination of a shell having a peripheral collection chamber with an annular throat opening into said shell, said throat having annular recesses in its side walls, and detachable relatively flat annular plates tting into said recessed walls and having flared edges projecting inwardly throat, means for removably securing said plates in position, an impeller in the shell havingthe walls of its peripheral delivery extended to run against the peripheral surfaces of theside plate projections to Jform 60 a joint tending to prevent leakage between them, the outer wall of said shell being removable whereby to obtain access to the interior of the shell and collection chamber, and said detachable wall having a flange constituting in eect a part of one wall of the said throat.

Y In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

GOMER W. PRICE.

Witnesses WM. F. Boorn, D. B. RICHARDS'.

and the construction is very durable. 40

beyond the walls of the 

